Device for working, particularly printing of sheet materials

ABSTRACT

A device particularly for the printing of sheet materials includes a rotating cylinder screen and a roller squeegee rotating within the cylinder screen. A supply of a liquid or viscous compound such as a dye adjacent the cylinder screen and the roller squeegee is forced through the cylinder screen to a sheet material to be printed. Torque transmitting driving means is provided for the cylinder screen as well as for the roller squeegee. The roller squeegee is driven at least approximately the same circumferential speed as the cylinder screen.

United States Patent [191 Zimmer 1 Jan. 14, 1975 DEVICE FOR WORKING,PARTICULARLY PRINTING OF SHEET MATERIALS [76] Inventor: Peter Zimmer,Untere Sparchen 54,

A 633 Kufstein, Austria [22] Filed: Sept. 27, 1973 [21] Appl. No.:401,252

Related US. Application Data [63] Continuation of Ser. No. 181,054,Sept. 16, 1971,

abandoned.

[52] US. Cl 101/119, 68/202, 101/120 [51] Int. Cl. B411 15/42, B4lf15/44 [58] Field of Search 101/119, 120,115, 116,

l0l/l23, 124, 121, 122', 68/200, 202

[56] References Cited UNITED STATES PATENTS l/1955 Dougherty et al.101/120 2/1966 Kramer 101/120 3,285,169 1l/l966 Hartwig 101/2073,487,775 l/l970 Chaney et a1. 101/114 3,625,144 l2/l97l Reinartzl0l/148 Primary Examiner-Robert E. Bagwill Assistant Examiner-R. E.Suter Attorney, Agent, or Firm-Wenderoth, Lind & Ponack [57] ABSTRACT 9Claims, 3 Drawing Figures PATENTEDJAN14|975 3.859.916

SHEET 10F 2 PETER ZIMMER INVENTOR Mum. @441 ATTORNEY s PAIENIEU3,859.916

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ATTORNEYS DEVICE FOR WORKING, PARTICULARLY PRINTING OF SHEET MATERIALSThis is a continuation application of application Ser. No. 181,054,filed Sept. 16, 1971, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to a deviceparticularly for the printing of sheet materials, wherein a liquid orviscous compound, such as a dye, is forced through a rotating cylinderscreen to a sheet material by means of a driven roller squeegee rotatingwithin the cylinder screen.

Such devices are generally used in rotary screen printing machines.However, the invention is not limited to squeegee rollers arrangedinside the printing cylinder of such machines, but may also be used forapplying a viscous liquid to a sheet-like material whereby the liquidmay be a dye which penetrates into the material or may be any substancewhich forms a coating on the material.

In known devices the squeegee roller is pressed against the innersurface of the cylinder screen. When the latter rotates, the rollersqueegee is put into rotation by friction between the roller and screen.Viscous liquid, in general dye, is fed into the interior of the screento such an extent as to form a sump beside the roller. On rotating, theroller takes the liquid along with it and squeezes it onto and throughthe screen onto the material to be printed. The pressure in the liquidwhich is created by the squeezing effect of the roller determines theamount of liquid fed to the material.

For this reason, the amount of the dye supplied to the material to beprinted in screen printing depends upon the pressure transmitted by theroller squeegee to the dye. With the known method, according to whichthe roller squeegee is rotated by frictional contact with the insidewall of the screen, the pressures produced in the dye or coatingcompound frequently are not sufficient to obtain a sufficientlyintensive application to the sheet material or a sufficient permeationby the dye of the sheet material, particularly if a relatively thicksheet material is used. Furthermore, it is a shortcoming that when theroller squeegee is rotated only due to friction with the screencylinder, the roller squeegee has to be pressed against the inside wallof the screen with relatively high pressure in order to insure that theroller squeegee is rotated. This relatively high contact pressure of theroller squeegee not only results in a considerable wear on the screenmaterial but also in a strong and sometimes detrimental deformation ofthe sheet material to be printed.

OBJECTS AND BRIEF DESCRIPTION OF THE PRESENT INVENTION It is an objectof the present invention to create a device, particularly for theprinting of sheet materials, the use of which has economic and technicaladvantages compared to known devices.

It is a further object of the present invention to create a deviceparticularly for the printing of sheet material which allows, withcareful treatment of the cylinder screen and relative slight contactpressure between the cylinder screen on the sheet material to be worked,a supply of flowable compound, such as a dye, which is also sufficientfor thicker material. This is effected according to the invention byproviding that the roller squeegee has positive drive means for drivingthe roller squeegee at least approximately at the same circumfer entialspeed as the cylinder screen.

A ratio of approximately 1:1 of the circumferential speeds of the rollersqueegee and the cylinder screen may be achieved by having the rollersqueegee driven by frictional contact with the cylinder screen. However, as already mentioned, this requires high contact pressure of theroller squeegee to prevent slippage from occurring. The high contactpressure also results in a considerable wear of the screen material. Theroller squeegee according to the present invention is separately drivento provide a ratio of 121 between the circumferential speeds of thecylinder screen and roller squeeges, but does not require high contactpressures to maintain this speed ratio, thus saving the screen materialas well as the sheet material to be worked.

The drive means of the roller squeegee may be provided with means toadjust the speed over wide ranges or by small incremental amounts, inorder to adjust as precisely as possible the circumferential speed ofthe roller squeegee to the value of the circumferential speed of thecylinder screen.

Embodiments of the invention are hereinafter described in detail withreference to the accompanying drawings without, however, being limitedthereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical longitudinalsection of the printing device of a rotary screen printing machineaccording to the present invention,

FIG. 2 is a cross section of the printing device of FIG. 1,

FIG. 3 is a partial longitudinal section of a modified embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION The cylinder screen 1 is formed asthe cylindrical screen printing stencil of the printing device of arotary screen printing machine according to FIGS. 1 and 2 and has endpieces 2 which are rotatably mounted in screen receivers, not shown inthe drawings, of the support of the machine.

At the left end piece 2 (as viewed in FIG. 1) there is a gear 3 whosepitch diameter exactly corresponds to the diameter of the screen. Thisgear 3 mates with a drive gear 4 which receives its movement from adrive means such as motor 5. Underneath the cylinder screen 1 there is aflexible printers blanket 6 supporting the sheet material 6' to beprinted and whose speed of movement corresponds to the circumferentialspeed of the driving gear 4. In the cylinder screen 1 there is a rollersqueegee 7 which is urged downwardly by electromagnets 8 within themagnet bar 9. The cylinder screen 1 moves in the direction of arrow 10during the printing operation. The roller squeegee 7 rotates at the sametime in the direction of arrow 11. During the rota tion of the cylinderscreen 1 and the roller squeegee 7, dye is applied from the supply orsump 7' adjacent the roller squeegee 7 on the upstream side thereofthrough the openings of the cylinder screen 1 to the sheet material 6'.The driving means of the roller squeegee 7 includes universal joints l2and a drive shaft 13 (or a flexible shaft) driven by a driving motor 14which are independent from the screen driving elements. Driving motor 14is mounted on a bracket or support 15. This driving motor is providedwith means to adjust the speed thereof over wide ranges and by smallincremencontact with screen 1 during rotation thereof. The fixing of thevertical position of roller squeegee 7 essentially is effected by thefield of the electromagnet 8.

- In the embodiment of the invention shown in FIG. 3, the drive means ofthe roller squeegee 7 in the inside of the cylinder screen 1 are formeddifferently than in FIGS. 1 and 2. Roller squeegee 7 is provided at oneend thereof with a pinion 20 mating with an inner annular gear 21 whichis mounted on one end piece 2 of the screen cylinder 1. When the pitchdiameter 22 of the which the roller has an independent means, andcontrary to FIG. 3 in which the roller is driven directly by thecylinder).

1 claim:

1. A device for the printing of a predetermined precise pattern on sheetmaterial with a liquid or'viscous printing compound, said devicecomprising:

a perforated cylinder screen mounted for rotation against said sheetmaterial;

means operatively connected to said cylinder screen for rotating saidcylinder screen at a desired circumferential speed;

a roller squeegee mounted for rotation within said cylinder screen tocontact the inner periphery thereof adjacent the line of contact betweensaid cylinder screen and said sheet material;

means operatively connected to said roller squeegee for rotating saidroller squeegee at the same circumferential speed as said cylinderscreen is rotated by said 'means for rotating said cylinder screen, tothereby avoid relative frictional rotation between said cylinder screenand said roller squeegee; and

means, separate from and not connected to said roller squeegee or saidmeans for rotating said roller squeegee, for supplying a liquid orviscous printing compound to a position adjacent said cylinder screenand said roller squeegee at the upstream side of said roller squeegee,whereby rotation of said roller squeegee and said cylinder screen forcessaid compound through the perforations in said cylinder screen and ontosaid sheet material without smearing said compound to thereby print saidpredetermined precise pattern on said sheet material.

2. A device as claimed in claim 1, wherein said means to rotate saidcylinder screen rotates said cylinder screen in the same direction assaid means to rotate said roller squeegee rotates said roller squeegee.

3. A device as claimed in claim 1, wherein said means for rotating saidcylinder screen comprises a gear attached to one end of said cylinderscreen, a drive gear engaging said gear, and a first adjustable speeddrive motor having a shaft supporting said drive gear.

4. A device as claimed in claim 3, wherein said means for rotating saidroller squeegee comprises a second adjustable speed drive motor, anddrive shaft means driven by said second drive motor and connected tosaid roller squeegee for transferring rotation of said second drivemotor to said roller squeegee.

5. A device as claimed in claim 4, wherein said drive shaft meanscomprises a shaftconnected between said roller squeegee and said seconddrive motor by universal joints.

6. A device as claimed in claim 4, wherein said drive shaft meanscomprises a flexible shaft.

7. A device as claimed in claim 3, wherein said means for rotating saidroller squeegee comprises a pinion connected to one end of said rollersqueegee, and

. means interconnecting said pinion and said cylinder screen. i

8. A device as claimed in claim 7, wherein said interconnecting meanscomprises an annular gear on the inner surface of said cylinder screen,said pinion meshing with said annular gear.

9. A device as claimed in claim 8, wherein the pitch diameter of saidannular gear equals the inner diameter of said cylinder screen, and thepitch diameter of said pinion equals the diameter of said rollersqueegee.

1. A device for the printing of a predetermined precise pattern on sheetmaterial with a liquid or viscous printing compound, said devicecomprising: a perforated cylinder screen mounted for rotation againstsaid sheet material; means operatively connected to said cylinder screenfor rotating said cylinder screen at a desired circumferential speed; aroller squeegee mounted for rotation within said cylinder screen tocontact the inner periphery thereof adjacent the line of contact betweensaid cylinder screen and said sheet material; means operativelyconnected to said roller squeegee for rotating said roller squeegee atthe same circumferential speed as said cylinder screen is rotated bysaid means for rotating said cylinder screen, to thereby avoid relativefrictional rotation between said cylinder screen and said rollersqueegee; and means, separate from and not connected to said rollersqueegee or said means for rotating said roller squeegee, for supplyinga liquid or viscous printing compound to a position adjacent saidcylinder screen and said roller squeegee at the upstream side of saidroller squeegee, whereby rotation of said roller squeegee and saidcylinder screen forces said compound through the perforations in saidcylinder screen and onto said sheet material without smearing saidcompound to thereby print said predetermined precise pattern on saidsheet material.
 2. A device as claimed in claim 1, wherein said means torotate said cylinder screen rotates said cylinder screen in the samedirection as said means to rotate said roller squeegee rotates saidroller squeegee.
 3. A device as claimed in claim 1, wherein said meansfor rotating said cylinder screen comprises a gear attached to one endof said cylinder screen, a drive gear engaging said gear, and a firstadjustable speed drive motor having a shaft supporting said drive gear.4. A device as claimed in claim 3, wherein said means for rotating saidroller squeegee comprises a second adjustable speed drive motor, anddrive shaft means driven by said second drive motor and connected tosaid roller squeegee for transferring rotation of said second drivemotor to said roller squeegee.
 5. A device as claimed in claim 4,wherein said drive shaft means comprises a shaft connected between saidroller squeegee and said second drive motor by universal joints.
 6. Adevice as claimed in claim 4, wherein said drive shaft means comprises aflexible shaft.
 7. A device as claimed in claim 3, wherein said meansfor rotating said roller squeegee comprises a pinion connected to oneend of said roller squeegee, and means interconnecting said pinion andsaid cylinder screen.
 8. A device as claimed in cLaim 7, wherein saidinterconnecting means comprises an annular gear on the inner surface ofsaid cylinder screen, said pinion meshing with said annular gear.
 9. Adevice as claimed in claim 8, wherein the pitch diameter of said annulargear equals the inner diameter of said cylinder screen, and the pitchdiameter of said pinion equals the diameter of said roller squeegee.